Method of welding lamp-filaments.



G. P. MORRISON. METHOD 0 1" WELDING LAMP PILAMENTS. v APPLIOATION EILBD MAB. 16, 1907. 1,093, 1 97.

fZ/l

Irv/@NUOV @sorge F Morrison by www Patented Apr. 14, 1914.

UNITED STATES PATENT OEEIQE.

GEORGE F. MORRISON, OF NEWARK, NEW JERSEY, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

METHOD OF WELDING LAMP-FILAMENTS.

To all whom it may concern Be it known that I, GEORGE F. MORRISON, a citizen of the United States, residing at Newark, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Methods of IVelding Lamp-Filaments, of which the following is a specification.

Incandescent lamp filaments can be attached to leading-in conductors or supporting wires by a welded or fused joint. Such connection insures good conductivity and a permanent junction between the filament and the wire. In case the filament consists of tungsten or other refractory material capable of operation at a very high temperature, a welded joint offers the advantage of freedom from carbonaceous pastevor binding material which might possibly combine with the material of the filament and lower its melting point.

According to my present invention, the lamp filament is welded to a metal wire by means of an electric arc, and magnetic means is utilized for deflecting the arc away from the filament, thereby protecting the filament from possible injury by the arc.

An apparatus suitable for carrying out my improved process of filament welding is shown in the accompanying drawing.

Figure 1 is a sectional elevation of a treating bottle in which the welding operation may be carried on; and Fig. 2 is an enlarged perspective view of the welding operation showing the position of the electromagnets which furnish the defiecting field for the arc.

In Fig. 1, the treating bottle or envelop 1 is arranged vertically and has an opening 2 through the top by which hydrogen or other non-oxidizing gas may be introduced. iVhen hydrogen is used, the lower end of the glass envelop may be open. The glass envelop is provided with tubular necks 3 and et through which the welding electrodes are manipulated. The tubular opening 3 is fitted with an insulating sleeve 5 in which is a brass block 6 connected by a binding post 7 with a source of electrical energy 8. Through brass block 6 passes a brass rod 9 having a handle 10 at the outer end and a carbon electrode 11 within the envelop. The other opening 4 is fitted with a tubular brass sleeve 12 electrically connected with the battery 8 and furnishing a pivotal sup- Specification of Letters Patent.

Application filed March 16, 1907.

Patented Apr. la, 1914.

Serial No. 362,621.'

port for a brass arm 13. The pivotal connection between arm 13 and block 12 is made tight, so that the arm will remain in any position to which it may be adjusted. The end of the arm is'provided with a notched socket 11 for engagement with the leadingin conductors which are to be welded to the filament.

The drawing illustrates alamp stem 15 having a central pedestal 16 and four lamp filaments 17 grouped around the pedestal and supplied with current through leadingin conductors 18 of platinum, nickel, or other suitable metal. For conveniently supporting this lamp structure in the treating bottle I make use of a rod 19 fitting in the hollow part of the socket. In carrying out the welding operation I place one of the leading-in conductors in the notch 14C and thereby connect the conductor with one side of the battery circuit. The carbon electrode 11 is then moved forward until it touches the leading-in conductor 18, preferably at the end of the hook with which the filament engages. The carbon electrode is then moved away to produce an arc which melts down the end of the leading-in conductor and forms a round globule of metal intimately contacting with the end of the filament. The atmosphere of hydrogen protects the filament from oxidation, but does not entirely protect the filament from the deteriorating action of the arc. I therefore make use of electromagnets 20 for developing a magnetic field having such a direction that the arc is deflected downward away from the filament. I do not wish to be limited to any specific construction or arrangement of the magnets but contemplate the use of any magnetic field capable of deflecting the welding arc away from the filament during the welding operation. In the drawing the electromagnets 20 are shown mounted on an iron strip 21 adj ustably supported by a suitable standard 22.

What I claim as new and desire to secure by Letters Patent of the United States, 1s,-

1. The method which consists in placing a filament in contact with a metal wire, drawing an are from said wire near the point of contact of said filament, and magnetically deflecting the arc away from said filament.

2. The process of connecting a filament to its current supply wire which consists in simultaneously clefleeting the are away from 10 the leg of said iilanient.

In witness whereof, I have hereunto set my hand this Sth clay of March, 1907.

GEO. F. MORRISON.

Vitnesses:

R. S. IYICNEIL, OHAS. II. I-IEELEY.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, I). C. 

